Espresso coffee machine

ABSTRACT

An espresso coffee machine including an electrically heatable water heater, a filter basket holder, and a filter basket holding device which can be sealingly closed by introducing therein the filter basket holder. The filter basket holder is subdividable by a filter into a brewing chamber that can be filled with coffee grounds and into a pouring device arranged at its bottom. The coffee machine further includes a first duct and a second duct having a steam outlet. The first duct opens into the filter basket holding device so as to connect the brewing chamber to the water heater and it includes a throughflow controlling valve arranged therein which is always closed when the filter basket holder is not inserted. After the filter basket holder is inserted into the machine, the filter basket holder causes the valve to move from its closed into an open position. There is also a first actuating member provided between the filter basket holder and the valve which is actuated by the filter basket holder to control the valve. Steam can be taken from the espresso coffee machine through the second duct in order to steam and froth beverages, the steam being produced in the water heater as well. In addition to the first actuating member, a second actuating member is provided which also serves to control the valve. The valve opens only if both the first and the second actuating member have adopted their open positions.

The present invention relates to an espresso coffee machine with anelectrically heatable water heater, with a filter basket holding devicewhich can be sealingly closed by introducing therein a filter basketholder, the said filter basket holder being subdivided by a filter intoa brewing chamber that can be filled with coffee grounds and into apouring device arranged at its bottom, the said brewing chamber beingconnectible to the water heater by a duct opening into the filter basketholding device.

Espresso coffee machines of this type have been selling for a long time.For instance, an espresso coffee machine is distributed by Messrs. SAECOs.r.l., Silla, Bologna, Italy, under the trade name "Bonjour moka",wherein the brewing chamber which is arranged in the filter basketholder and can be filled with coffee grounds links to a duct that opensinto the filter basket holding device and, in turn, connects to anelectrically operated water heater producing hot water. Interposed inthe duct between the brewing chamber and the water heater is athroughflow controlling valve that is adapted to be opened or closed,respectively, by hand through an actuating member designed as a turninglever on the top side of the housing, in order to open or close thesupply of hot water into the brewing chamber. The water heater in thisespresso coffee machine is an electrically heatable air-pressure tankwhich, in the presence of excess pressure, pumps boiling water oroverheated steam to the brewing chamber.

By way of actuating the turning lever, the valve can adopt its closedposition in this espresso coffee machine so that no water is deliveredto the brewing chamber. This position is chosen by the user when it isdesired to discharge steam out of the steam boiler via the steam pipe,with the steam valve arranged at the rear area of the housing beingopen. For instance, when the steam pipe is then immersed into cold milk,this milk will be steamed and simultaneously frothed so that thick andfrothy cappuccino results after espresso coffee has been added. However,the valve must be closed also in the event that, after an espressocoffee has been prepared, the filter basket holder shall be removedsafely from the filter basket holding device, with no hot watercontinuing to flow out of the filter basket holding device.

If in this espresso coffee machine--shortly after e.g. milk has beenfrothed and the steam valve has been closed--the valve serving for thethroughflow control is opened by swinging up the turning lever, hotwater and finally hot steam, too, can exit explosion-like out of thefilter basket holding device due to the prevailing pressure in the steamboiler, if the filter basket holder has not been introduced in thefilter basket holding device. The explosion-like deflagration is stillmagnified by the fact that the water heated to roughly 120 to 130degrees Celsius in part will evaporate abruptly when it enters theatmosphere. This large-surface deflagration of hot water or steam,respectively, may cause unpleasant burns on the hand of a user. However,this may also occur in those instances when a user removes the filterbasket holder from the filter basket holding device or places it thereonwithout having closed the valve beforehand.

In the espresso coffee machine "Espresso GAGGIA" of Messrs. BREVETTIGAGGIA Spa. Robecco/Naviglio, too, hot water will exit from the filterbasket holding device, namely in the event that the electric pumpgoverning the throughflow control is switched on by turning on the pumpswitch and the filter basket holder is not introduced into the filterbasket holding device. This happens also on heating up of the machine,since the fast heating up causes the expanding water which oftenentrains hot steam to exit from the filter basket holding device. Thismay also cause burns on the hand.

Therefore, it is an object of the present invention to improve upon anespresso coffee machine, no matter whether it is operated by a pump orby a steam boiler, to such effect that, if the filter basket holder isnot inserted, it is prevented that brewing water or overheated steamwill exit from the filter basket holding device, and that boiling wateror overheated steam may exit from the filter basket holder only if saidhas been properly inserted into the filter basket holding device.

This object is achieved by the present invention in that a throughflowcontrolling valve is arranged in the duct in a manner known per se, inthat the valve is always closed when the filter basket holder is notinserted, and in that, after the insertion of the filter basket holder,the latter causes the valve to assume its open position. Owing to thepresent invention, a safety arrangement is obtained which permits hotwater to exit from the filter basket holding device only after thefilter basket holder has been properly inserted into the filter basketholding device, which water may enter into the brewing chamber of thefilter basket holder, from where--after brewing water has been poured onthe espresso coffee grounds--the espresso coffee flows through thefilter and leaves through the pouring device the filter basket holder,from where it is finally conveyed into a cup positioned underneath thefilter basket holder.

Such a safety arrangement according to the present invention can be madeuse of both in pump-operated and in steam-boiler-operated espressocoffee machines. Steam or hot water pouring out of the filter basketholding device in all directions, what very often takes place in anexplosion-like deflagration, is avoided by the present invention, sothat there will be no more unpleasant burns if a hand remainsinadvertently in the area underneath the filter basket holding device.Opening of the valve can be effected directly by the filter basketholder or by any other electrical or mechanical transmission members tobe activated by the filter basket holder. Even if the user hasintroduced the filter basket holder into the filter basket holdingdevice, it is admitted that hot water can pour out of the pouring deviceprovided on the filter basket holder, but due to the pouring devicehaving a comparatively small diameter this by far not as dangerous aswith the larger opening formed at the filter basket holding device whichhas an exhaust aperture many times larger.

It is only scarcely possible in many cases to position the valveassembly in the filter basket holding device such that the valve can bebrought into direct contact with the filter basket holder. It isadvantageous in these cases in an improvement upon the present inventionthat a first actuating member is provided between the filter basketholder and the valve which is actuated by the filter basket holder tocontrol the valve. A mechanical connection between the filter basketholder and the valve is established by the first actuating memberprovided independently of the filter basket holder in the filter basketholding device. In this embodiment, the valve can be arranged in theduct at any location desired. However, the first actuating member canalso be an electric switch, for instance, adapted to be activated by thefilter basket holder and controlling an electromagnet which actuates thevalve. Instead of a purely mechanical solution, this would be anelectromechanical solution which will not be dealt with more closely inthe present invention though.

It is particularly favourable that the introduction of the filter basketholder is performed by an axial displacement directed towards the filterbasket holding device, that the first actuating member is a turninglever, the one end of which is so pivoted about its point of support dueto the axial displacement which occurs when the filter basket holdingdevice is closed by the filter basket holder, that, in doing so, anactuating element formed at the turning lever opens the valve. That isto say, the axial displacement occurring when the filter basket holderis locked at the filter basket holding device is made use of foractuating the valve in this embodiment. This axial displacement can beproduced, for instance, when the filter basket holder is fastened by athread arrangement or ramp arrangement between the filter basket holderand the filter basket holding device. However, other possibilities ofattachment are also possible, yet it is mandatory that an axialdisplacement results when the filter basket holder is attached andsealed in the filter basket holding device.

Favourably, the filter basket holder is inserted in that it is turned bymeans of projections into a thread or into a bayonet lock arrangement,in that the first actuating member is a first lever rotatable about anaxis, whose free end is rotated about its axis by the closing movementof the filter basket holder such that a first actuating element providedon the first lever opens the valve. A like valve actuation can berealised particularly easily in conventional espresso coffee machines,since the filter basket holder is normally coupled to the filter basketholding device by way of a bayonet lock arrangement, which permits toquickly insert and lock the filter basket holder so that a rotatingmovement results automatically. This rotating movement will then betransmitted directly to the first lever so that said follows a rotatingmovement as well. A turning lever offers the further advantage thatsmall valve piston travels can be covered even in the event of largerangles of rotation at the filter basket holder and thus also at thefirst lever. This is because large angles of rotation at the first leverpermit the user to recognize from far away the position the first leverhas adopted, i.e. whether it is in the position in which the valve isopen or that in which the valve is closed.

When the filter basket holder is inserted, the free end of the firstlever is engaged in a recess shaped at it according to an improvementupon the present invention. It is always ensured due to this forcedguidance of the free end of the first lever on the filter basket holderthat, on turning of the filter basket holder, no matter whether into theremoval position or into the closing position, the first lever, too, isindeed turned in conformity with the turning of the filter basketholder.

In another embodiment, the first lever is entrained only in thedirection of the valve closing position, e.g. by the filter basket. Itis favourable in this event that a spring makes catch at the first leverwhich automatically restores the first lever into its initial positionclosing the valve, when the filter basket holder is detached from thefilter basket holding device. Even in the event of a forced guidance ofthe lever, as has been described hereinabove, a spring causing the leverto assume its initial position can be advantageous, in order that thelever will not move into its centre position in case the espresso coffeemachine is exposed to vibrations, so that the engagement of the free endof the lever in the recess would be possible no more.

It is expedient that the valve is formed by a valve piston which isaxially slidable in the housing of the filter basket holding device andby a valve seat opened and closed, respectively, by the valve piston,that the valve piston is acted upon by a spring for the purpose ofautomatic opening of the valve, that the valve piston with its free endprojects from the housing of the filter basket holding device and issealed in relation to the housing, that, with the valve closed, thefirst actuating element designed on the first lever abuts on the freeend of the piston and presses said against the valve seat in the housingof the filter basket holding device, while, for opening that valve, thefree end of the first lever is turned by the filter basket holder suchthat the first actuating element moves out of the range of effect of thevalve piston and the valve piston lifts from the valve seat. That is tosay, in this valve assembly, the actuating element of the first levermust press constantly on the free end of the valve piston, in order tourge said to sealingly rest on the valve seat, whereby the passage ofthe duct to the brewing chamber is interrupted. As soon as the actuatingelement of the first lever releases the valve piston, the valve pistonwill lift from the valve seat under the action of spring force and opensthe passage from the first duct to the brewing chamber arranged in thefilter basket holder so that an espresso coffee beverage can be made.

Slow opening and closing, respectively, of the valve is achieved in afavourable manner in that the area of the actuating element on the firstlever facing the free end of the valve piston is a slide configured as afirst ramp, and in that the first ramp increases its distance to thefree end of the valve piston in the closing direction of the filterbasket holder. Depending on how large the inclination of the first rampis chosen to be, the valve can open or close quickly or more slowlydepending on the angle of rotation of the first lever.

To prevent the valve piston, which is subjected to the force of thespring in the opening direction, from turning the first lever into theopening position releasing the valve, without the user having actuatedthe first lever, and in order that, simultaneously, the valve piston inits opening position will not jump out of its guide bore, it is arrangedfor in an improvement upon the present invention that adjacent to thefirst ramp on both sides is a slide in the form of abutment surfaces,which extend perpendicular to the longitudinal axis of the valve piston,and that the two horizontally extending abutment surfaces are disposedwithin the closing angle of the filter basket holder. The longitudinalaxis of the valve piston may be inclined to a certain degree in relationto the slide. The only thing important is that, when the slide makescatch at the valve piston, the latter will still adopt its closing oropening position, respectively.

A particularly simple and low-cost arrangement of the valve assemblyresults in that the first lever extends substantially perpendicular tothe longitudinal axis of the valve piston and the axis of the firstlever, in that the free end of the first lever extending towards thefilter basket holder is angled off in relation to the horizontallyextending area of the first lever and extends in parallel to thelongitudinal axis of the piston and the axis of the first lever, and inthat the free end is movable into operative engagement with a stopdesigned on the filter basket holder, which is arranged on the filterbasket holder radially outside a sealing joint at the filter basketholding device. From this ensues a particularly simple and easy assemblywhich avoids undesirable transverse forces on the movable parts.Simultaneously, the direct conversion of force brings about a valveassembly which affords ease of motion and long useful life.

There being no need to carry out modifications compared to the seriesproduction design, the lever assembly is designed such that the filterbasket holder is adapted to be coupled to the filter basket holdingdevice by way of a bayonet lock arrangement, and such that the bayonetlock element on the side of the filter basket holder forms the stop forthe free end of the first lever.

Since steam, too, is produced in the up-to-date steam-boiler-operatedespresso coffee machines which is almost imperative for the additionalpreparation of cappuccino, it is suggested in an improvement upon thepresent invention that steam can be taken from the espresso coffeemachine through a second duct provided with a steam outlet for thepurpose of steaming and frothing beverages, the said steam likewisebeing produced in the water heater, that, in addition to the firstactuating member, a second actuating member is provided which alsoserves to control the valve, and that the valve opens only if both thefirst and the second actuating member have adopted their open position.

The second lever which, for a steam-boiler-operated espresso coffeemachine, acts upon the valve in addition to the first lever will permitopening of the valve--although the first lever has been caused by thefilter basket holder to assume its position opening the valve--only ifit has been caused to assume its position opening the valve as well.That is to say, if the filter basket holder is not introduced into thefilter basket holding device, the first lever cannot be actuated by thefilter basket holder, and the second lever, even it if has assumed itsopening position, cannot bring about opening of the valve, since thefirst lever continues to keep the valve closed, even if the second leverin its opening position opens the valve. Consequently, steam cannot pourout of the filter basket holding device in the closed position of thevalve, it is merely allowed that steam flows to the steam outlet openingserving to prepare cappuccino, however, this being possible only if thesteam valve is open which is provided additionally at the second duct.

Since the steam pressure and, thus, the temperature in the steam boilerare controlled by a thermostat, inadmissibly high steam pressure cannotdevelop in the steam boiler, not even if the steam valve and the valveare closed. Should this occur nevertheless, a pressure-relief valve isprovided as a safety means on the cover closing the steam boiler,through which latter valve the excessively high pressure is thendischarged into the atmosphere.

There is no need for a second actuating member according to the presentinvention in those pump-operated espresso coffee machines, in whichsteam is produced in a steam heater that is designed independently ofthe water heater and produces steam only in the event that water flowsthrough a drip valve coupled to the water tank into the steam heater,from where it flows as steam through the second duct, which is notlinked to the first duct to the steam outlet. For this reason, allimprovements upon this invention which concern the second lever areintended for use in steam-boiler-operated espresso coffee machines only.

According to a first design variant of the valve of the instantinvention, the first and the second actuating member comprises a firstand, respectively, a second actuating element which can be brought intocontact with the valve, the filter basket holder being inserted in thatit can be turned by way of projections into a thread or into a bayonetlock arrangement, the first and the second actuating member being afirst and a second lever rotatable about a first axis, the valve beingformed by a valve piston axially slidable in the housing of the filterbasket holding device and by a valve seat opened and, respectively,closed by the valve piston, the said valve piston being acted upon by aspring for the purpose of automatic opening of the valve, and the valvepiston at its free end being adapted to be acted .upon by each one firstand second actuating element designed on the first and the second lever,the valve being sealed in relation to the housing, wherein, with thevalve closed, the first and, respectively, the second actuating elementabut with preload on the free end of the valve piston, while, foropening .the valve, the first and the second actuating element aredisposed outside the range of effect of the free end of the valve pistonby the free end of the first lever being turned by the filter basketholder, and by the second actuating element, when turned by hand, alsomoving out of the range of effect of the valve piston.

For closing the valve, the valve piston in this valve assembly ispressed into the housing by the first and, respectively, the secondactuating element in opposition to the preloading force of the spring.As soon as both actuating elements move out of the range of effect ofthe valve piston, that means they no longer keep it in its closedposition, it will detach automatically from the sealing seat caused bythe preloading force of the spring and move a distance out of thehousing. In doing so, it releases the duct so that water may flow out ofthe pressure tank through the duct to exit at the filter basket holdingdevice, where it is pumped by the steam boiler pressure into the brewingchamber filled with espresso coffee grounds.

To be able to accomplish a longitudinal displacement of the valve pistonby minimum lever force, and in order to attain a movement of the valvepiston directed into the housing for the purpose of closing the valve, afirst and, respectively, a second slide designed as a ramp are providedboth at the first and the second actuating element in the area close tothe free end of the valve piston, the distance of the first and thesecond slide increasing in relation to the free end of the valve pistonin the closing direction of the filter basket holder.

In order that possibly both ramps abut with the same force on the valvepiston in the closed position of the valve and that, consequently, onturning out of one lever the other lever continues to reliably close thevalve, the first and the second ramp extend substantially in the sameplane and in parallel to each other in the closing position of the firstand the second lever.

Owing to the slide seat arrangement between the valve piston and theactuating elements, the actuating members can be mounted particularlyeasily in the filter basket holding device, since the levers merely haveto be slipped and axially secured on their axes. When the second leveris pivoted on a second axis provided on the first lever, and when theramps of the first and the second lever configured as slides extendconcentrically relative to each other, opposite to the free end of thevalve piston and radially one behind the other, when viewed from theaxis, only one axis is required on the filter basket holding device forsupporting the levers. The slides are arranged such in relation to thevalve piston in the closed position of the valve that the firstactuating element, when viewed from the axis, beyond the centre line ofthe valve piston abuts on said's free end, while the second actuatingelement on this side of the centre line of the valve piston abuts onsaid's free end.

In order that a user can freely choose, whether to produce steam inorder to heat up a beverage and to froth it at the same time, or whetherto produce hot water for preparing an espresso coffee, it is favourablethat the second lever can be operated by hand.

To keep the overall height of the valve assembly and hence also theoverall height of the filter basket holding device as small as possible,it is advantageous that the first axis is formed by a peg, on which thefirst lever is supported by way of a first bore, and that the firstlever comprises a cylindrical peripheral surface on the outside wall ofthe first bore, on which surface the second lever is supported by way ofa second bore provided on the second lever. Owing to the two actuatingmembers being supported on only one axis, the design and the mounting ofthe valve assembly will be facilitated greatly.

In an improvement upon the present invention, it is proposed that thefirst lever is supported on the first axis above the second lever, andthat, outside the second lever, a first projection is formed on thefirst lever in the area of the valve piston, which projection representsthe first actuating element, which is directed towards the valve pistonand on the end surface of which close to the valve piston the first rampis provided. The first lever extending over the second lever permits thesecond lever to take support on a comparatively large surface on thefirst lever in the opening direction of the valve piston so thatpossibly occurring transverse forces will not result in the second levergetting hooked. It is also rendered possible hereby that the free end ofthe first lever can be arranged to be offset in relation to the free endof the second lever, thereby permitting ease of coupling to the filterbasket holder.

To allow the second lever to be provided on the front side of theespresso coffee machine for ease of handling, and to prevent it fromcolliding with the first lever, it is expedient that the distancebetween the second ramp of the second lever and the first axis is lessthan the distance between the first ramp of the first lever and thefirst axis.

In a second embodiment of the valve assembly and the actuating devicedepending on it, it is proposed in a favourable manner that the firstand the second actuating member comprises a first and, respectively, asecond actuating element controlling the valve, that the filter basketholder is inserted by being turned by way of projections into a threador a bayonet lock arrangement, that the first and the second actuatingmember is formed by a first and a second lever rotatable about an axis,that the valve is formed by a valve piston axially slidable in thehousing of the filter basket holding device and by a valve seat openedand closed, respectively, by the valve piston, that the valve piston isacted upon by a spring for the purpose of automatic closing of thevalve, that on its free end the valve piston can be acted upon by eachone first and second actuating element provided on the first and thesecond lever, that the valve is sealed in relation to the housing, thatthe first lever is additionally arranged to be slidable towards thevalve piston, that, when after one of the two levers has been turnedinto the position serving to open the valve, the other lever, too, isturned to assume the opening position serving to open the valve, bothactuating elements of the levers act upon each other such that the firstlever is displaced in the opening direction of the valve piston on asecond axis arranged on the second lever, thereby opening the valve.

That is to say, in this second embodiment of the valve assembly, thevalve piston is moved in exactly the opposite direction compared to thefirst embodiment for the purpose of opening the valve. The advantage isthat, if the valve piston is stuck fast or is jammed tight in the valvebore in the event of non-use of the espresso coffee machine for a longerperiod of time, the valve piston will be forced by the first actuatingmember to shift into its open position for opening the valve, when thesecond member has already adopted its position opening the valve. Thevalve piston will free itself from its impeded motion in the valve boreso that, subsequently, it can move on its own again to assume itsclosing position caused by the preloading force of the spring, once thetwo actuating members are turned out of the range of effect of the valvepiston.

While in the first embodiment of the valve assembly the two actuatingelements are arranged side by side irrespective of one another, thatmeans opposite to the valve piston, in the second embodiment of thevalve assembly, the two actuating elements are arranged one behind theother in the longitudinal direction of the valve piston, and thatactuating element which is turned the last into its position opening thevalve is shifted inbetween like a wedge, so that the first actuatingmember is displaced in the longitudinal direction of the valve pistonand, in doing so, slides the valve piston into its valve bore. As aresult, the sealing seat provided on the valve piston lifts from thesealing seat formed in the housing, and the duct to the brewing chamberis released.

Since the first actuating member is turned in a concealed fashion whenthe filter basket holder is inserted and, in the event that the firstlever has already assumed its ready position opening the valve, i.e. isin the espresso coffee making mode, since it is simultaneously displacedin a concealed fashion in the longitudinal direction of the valve pistonwith a view to opening the valve, this course of motion will not concernthe outer contour of the espresso coffee machine, since the first leveris integrated in the housing of the filter basket holding device to beinaccessible from the outside.

In order to bring about in a simple fashion an axial longitudinal shifton the first actuating element that is directed towards the valvepiston, it is arranged for in an improvement upon the present inventionthat the area of the first actuating element on the first lever close tothe second lever is a first slide configured as a first ramp, and thatthe first ramp is descending when viewed in the closing direction of thefilter basket holder. It is an advantage of the first ramp provided onthe first lever that, with a very insignificant descent, the valve, too,opens but very slowly in dependence on the angle of rotation of thefilter basket holder. For instance, if the steam boiler is subjected toits maximum operating pressure, the brewing water will not flow abruptlyinto the brewing chamber when the valve is opening slowly, so thatundesirable turbulences in the espresso coffee grounds are avoided. Thisis because flow stress ratios similar to those in a pump-operatedespresso coffee machine are to be attained by the slow opening of thevalve.

When the first or the second lever or both together are turned, thefirst ramp formed on the first lever will slide along an edge or surfaceprovided on the second lever, so that the first lever is displaced inaxial direction towards the valve piston and thereby moves said toassume its opening position. However, it is of course also possiblethat, instead of the first ramp being provided on the first lever, itcan also be provided on the second lever, whereby eventually the sameresult will be obtained.

It is particularly favourable that, in addition to the first rampprovided on the first lever, a second slide configured as a second rampis provided on the area of the second lever that is close to the firstlever, and that the second ramp extends substantially in parallel to thefirst ramp. Owing to the ramps sliding on each other, both levers can beactuated especially easily by little rotational force.

According to an improvement upon the present invention, the second leveris pivoted directly on the first axis, and the first lever is pivoted ona second axis arranged on the second lever. That is to say, in thissecond embodiment of the lever assembly, the first lever is supportedthrough a second axis arranged on the second lever, and the lattersecond lever, in turn, is supported on the first axis on the filterbasket holding device, while this is just vice-versa in the firstembodiment. Consequently, it is exclusively the first lever whichestablishes the contact with the valve piston in the second embodiment,whereas in the first embodiment both levers can act directly on thevalve piston.

If a ramp is provided on only one of the two levers, both levers canhave the same direction of rotation for opening the valve. If, however,ramps are provided on both levers, the direction of rotation of thefirst lever is opposite to the direction of rotation of the second leverfor opening the valve, in order to permit the ramps to move towards eachother and to get into operative engagement so that they can slide oneach other.

To permit the first lever to be actuated at all by the filter basketholder, it must extend up to the range of effect of the filter basketholder. It is favourable that the first lever extends substantiallyperpendicular to the longitudinal axis of the valve piston and the firstaxis of the first lever, that the free end of the first lever extendingto the filter basket holder is angled off in relation to thehorizontally extending area of the first lever and extends in parallelto the longitudinal axis of the piston and the first axis of the secondlever, and that the free end is movable into operative engagement with astop provided on the filter basket holder, the said stop being arrangedon the filter basket holder radially outside a sealing connectionprovided on the filter basket holding device. Since the first lever withits angled-off free end displaces towards the valve piston in the secondembodiment, there must be free space for this area at the filter basketholding device.

In order to avoid an explosion-like exit of the water on the valve whensaid is opened quickly, for instance, if the inclination of the rampswas chosen to be comparatively steep, according to an improvement uponthe present invention, a throttle designed as a reducing valve isarranged in the valve or downstream thereof in the first duct towardsthe brewing chamber. The said throttle may also be formed by the valveitself in that the opening cross-section of the valve is sized but solarge that an explosion-like deflagration of the water under pressurewhen exiting into the brewing chamber is avoided.

Several embodiments of the present invention are illustrated in thedrawings and will be explained in more detail hereinbelow. In thedrawings,

FIG. 1 is a longitudinal cross-section of a filter basket holding deviceof an espresso coffee machine taken along the line of intersection I--Iof FIG. 4 according to a first embodiment, wherein both levers actdirectly upon the valve piston and keep it in its closed positionagainst the force of a spring, and wherein the free end of the firstlever has been turned into the drawing's plane,

FIG. 2 is a filter basket holding device according to FIG. 1, however,with a second embodiment of a lever and valve assembly, wherein only onelever acts directly upon the valve piston, and wherein the valve reachesits closed position only when the first lever does not exert force onthe valve piston,

FIG. 3 is a longitudinal cross-section through a second valve modifiedin comparison with the second embodiment according to FIG. 2, the filterbasket holding device being illustrated in outlines only,

FIG. 4 is a cross-section taken along the line of intersection IV--IV inFIG. 1, wherein the two levers keep the valve in its closed position,and wherein the filter basket holder disposed farther below and part ofthe filter basket holding device are illustrated in outlines only,

FIG. 5 is a cross-section through the second actuating element with itssecond ramp, provided on the second lever,

FIG. 6 is a cross-section through the first actuating element with itsfirst ramp, provided on the first lever,

FIG. 7 is a cross-section taken through the two actuating elements ofthe two levers taken along the line of intersection X--X in FIG. 2,wherein the filter basket holder is inserted properly into the filterbasket holding device and, simultaneously, the second lever has adoptedthe position for espresso coffee making,

FIG. 8 is a partial cross-section according to FIG. 7, however, thedifference being that the lever is in the steam operation position,

FIG. 9 is a partial cross-section according to FIG. 7, however, thedifference being that the filter basket holder is not inserted into thefilter basket holding device and the second lever is in the position formaking espresso coffee nevertheless, and

FIG. 10 is a partial cross-section according to FIG. 9, however, thedifference being that the second lever is in the steam operationposition.

FIGS. 1 to 3 illustrate in a longitudinal cross-sectional view only thatportion of the filter basket holding device 2 of the espresso coffeemachine that is disposed above the filter basket holder 1. The otherparts of the espresso coffee machine such as e.g. steam boiler, heating,steam boiler cover, steam duct for producing steam, switch, housingetc., have not been illustrated for the sake of simplicity, since theyconcern the actual invention only marginally. To avoid repetitions,identically functioning component parts have been assigned likereference numerals in FIGS. 1 to 10.

The filter basket holder 1 is substantially of bowl-shaped design andcontains in its bottom 3 at least one outlet 4, which serves as apouring device and from which the espresso coffee made pours out into acup placed below the filter basket holder 1 that is not either shownherein. A bowl-shaped filter basket 4 is placed in the filter basketholder 1 which has in its bottom 6 a plurality of small-diameterpassages 7 and forms the actual filter of the espresso coffee machine.Instead of the filter basket 5, of course, the present invention alsopermits to introduce a filter screen into the filter basket holder sothat a filter screen holder is also meant by the term filter basketholder.

In FIG. 1, the chamber 8 formed by the filter basket 5 serves to receivethe espresso coffee grounds and, thus, forms the actual brewing chamber8, which is isolated from the pouring device 4 by the filter basket 5.At its upper end in the drawing, this filter basket 5 is provided withan outwardly directed annular collar 9, which abuts on the upper end onthe front surface 10 of the filter basket holder 1 and takes supportthereon, so that the bottom 6 of the filter basket 5 furnished with thepassages 7 will always be at a certain distance from the bottom 3 of thefilter basket holder 1.

According to FIGS. 1 and 4, the outside periphery of the upper rim ofthe filter basket holder 1 is provided with radially protruding andcircle-ring-segment-shaped projections 11, which are engaged into grooveportions 12 shaped on the filter basket holding device 2. Theseprojections 11 together with the groove portions 12 form the bayonetlock arrangement, which is provided in filter basket holders 1 ofespresso coffee machines in a manner known per se, due to which, oninsertion of the filter basket holder 1 and its subsequent turning inthe filter basket holding device 2, the end surface 10 according to FIG.1 is displaced axially in the longitudinal direction of the centre line13 upwardly so far that the annular collar 9 is pressed into sealingabutment on a ring seal 14 attached to the filter basket holder 1, sothat the brewing chamber is sealingly connected with the filter basketholding device 2.

The ring seal 14 of FIG. 1 contains a central bore 15, into which asecond filter 16 is inserted which, in turn, is held in the filterbasket holding device 2 by a screw 17 and which, together with the bore,forms a distribution chamber 61. Since the second filter 16 according toFIG. 1 abuts from the bottom against an annular collar 18 which isarranged on the ring seal 14 and serves as a stop, the ring seal 14 islikewise retained in position on the filter basket holding device 2through the filter 16 and the screw 17. The second filter 16 confinesthe brewing chamber 8 towards the filter basket holding device 2 and, onthe one hand, is meant to provide that the brewing water dripping fromthe top through the distribution chamber 61 onto the second filter 16 isdistributed evenly over the surface of the second filter 16, so that itcan enter under pressure over a large surface into the brewing chamber8. On the other hand, contamination caused by the espresso coffeegrounds at the valve assembly 19, that is provided in the filter basketholding device 2, and in the supply duct 26 is avoided.

The valve assembly 19 in FIG. 1 consists of a valve bore 20 whichextends in parallel to the centre line 13 and above the second filter 16in the filter basket holding device 2, in which bore a valve piston 22is arranged axially slidably that is sealed in relation to the valvebore 20 by means of a ring seal 21. The ring seal 21 is secured to thevalve piston 22 above an inlet opening 57 which connects the first duct26 via a valve chamber 58 with the valve seats 32, 33. The valve bore 20is not shaped directly in the filter basket holding device, it ratherextends in a cover 23 which is fastened in a stepped bore 24 provided inthe filter basket holding device 2 sealed by means of a seal 25. At itslarger diameter, the stepped bore 24 is connected through a first duct26 with a steam boiler not illustrated in the drawing, and it reaches inthe steam boiler until close to the bottom, in order to ensure that,even at a minimum water level, it is not steam but already water whichis supplied to the first duct 26.

The end of the stepped bore 24 directed to the second filter 16comprises a smaller-diameter annular step 27 which, simultaneously,forms the end of the stepped bore 24 representing the inlet to thebrewing chamber 8. Abutting pressure-tightly on the annular surface 28of the annular step 27 facing the valve piston 22 is a ring seal 29,which is kept in abutment on the annular surface 28 by a compressionspring 30 that is supported under preload on an annular collar 31 formedon the valve piston 22.

The valve piston 22 penetrates the cover 23 in FIG. 1 through the valvebore 20 upwardly and comprises at its free end a convexly extendingslide, on which both a first and a second actuating element 34 and 35being configured as a first and a second ramp are abutting such that thevalve piston 22 is pressed with its sealing seat 32 against the sealingseat 33 in opposition to the force of the compression spring 30, so thatthe duct 26 from the steam boiler to the brewing chamber 8 is closed.

The first ramp 34 is provided on the first lever 36 which, in turn, byway of a first bore 37 formed on it is pivoted on a peripheral surface64 of a first axis 38 shaped as a peg and projecting upwardly from thecover 23 in FIG. 1. The first axis 38 extends substantially in parallelto the longitudinal axis 39 of the valve piston 22. The first lever 36extends above the cover 23 substantially perpendicular to thelongitudinal axis 39 of the valve piston 22.

In the right-hand area in FIG. 1, the free end 40 of the first lever 36is angled off and extends substantially in parallel to .the longitudinalaxis 39 of the valve piston 22. For the sake of simplicity, the free end40 was placed into the drawing's plane, in order to be able toillustrate in one single cross-section also the course of the entirefirst lever 36. In reality, the free end 40 extends as is shown in FIG.4. This free end 40 extends through a slot 41 formed in the filterbasket holding device 2 and reaches the range of effect of a projection11 shaped on the filter basket holder 1, once it is inserted into thefilter basket holding device 2. The first ramp 34 is provided on aprojection 43, which is arranged on the right side of the longitudinalaxis 39 and is directed to the free end 42 of the valve piston 22 inFIG. 1.

According to FIGS. 1 and 4, a second lever 45 is pivoted below the firstlever 36 on said's outside surface 44 forming the first bore 37 by wayof a second bore 46 formed on a tubular portion 74. Hence the outsidesurface 44 serves as a second bearing axis of the second lever 45. Onthe right side of the centre line 13 of the axis 38, the secondactuating element 35 abutting on the free end 42 of the valve piston 22is designed on the second lever 45, the second abutment surface 73 ofthe said actuating element abutting on the free end 42 only in theclosing position of the second lever 45 illustrated herein and likewisepressing the valve piston 22 against the valve seat 33. What is meant bythe closing position of the first and the second lever 36 and 45,respectively, is that position in which the valve assembly 19 is closed.

While the first ramp 34 and the horizontally extending abutment surface70 adjacent to the ramp 34 are arranged to the right of the centre line39 of the valve piston 22 according to FIG. 1, the second ramp 35 andthe horizontally extending abutment surfaces 72, 73 adjacent to the ramp35 extend to the left of the longitudinal axis 39 of the valve piston22. The horizontally extending line 71 in FIG. 1, which is shown inphantom lines on the first projection 43, represents the bottom end(FIG. 6) of the first ramp 34, from where a third abutment surface 71may extend to the left, while the line 70 represents the upper end ofthe first ramp 34, from where the first abutment surface 70 succeeds tothe right. The same applies to the second and fourth abutment surface73, 72 adjoining on the second lever 45 on both sides of the second ramp35. These abutment surfaces 70 to 73 serve for locking and bounding thevalve piston 22 and the two levers 36, 45.

However, it is also possible that an abutment surface 70, 73 is providedon the first and the second lever 35, 45 for locking the valve piston 22according to FIGS. 1 and 4 only in the position closing the valveassembly 19. That is to say, the abutment surface 72 arranged accordingto FIG. 4 on the other end of the second leg 68 serves to prevent thevalve piston 22 from sliding out of the valve bore 20 in the openposition of the valve 19. The third abutment surface 71 is thus formedon the first leg 65 of the first lever 36 solely by an edge, since it isnot required when there is provision of the fourth abutment surface 72.However, in the absence of the fourth abutment surface 72, the thirdabutment surface 71 in full length is necessary corresponding to themaximum angle of rotation of the second lever 45 into its positionrequired to produce steam. If, on the other hand, the valve piston 22 issecured against dropping out, neither the abutment surface 71 nor theabutment surface 72 is needed.

In order to secure the two levers 36, 45 axially in position on thefirst axis 38, a screw 48 is turned into a threaded bore 47 at the freeend of the axis 38 and secures the first lever 36 axially on the cover23 by way of a safety element 49. The first lever 36 also secures thesecond lever 45 axially in the position illustrated in FIG. 1, or,respectively, retains its end surface 69 in abutment on, or in closeproximity to, an annular step 54 provided on the cover 23, on which stepalso the end surface 66 of the first lever 36 takes support. The secondlever 45 projects with its free end 50 through an opening 52 out of thehousing 51, which confines the filter basket holding device 2 upwardlyand laterally, so that the second lever 45 can be operated by hand byvirtue of the free end 50 forming the handle.

The filter basket holding device 2 illustrated in FIG. 2 differs fromthat in FIG. 1 only in that a differently constructed valve assembly 19and, related thereto, a variation of the lever assemblies 36 and 45 havebeen chosen. The valve seat 33 on the housing is arranged on a tubularend 55 provided on the cover 23, while on the end's area close to theannular step 27 the valve seat 32 extends conically and tapers upwardly,when viewed in the drawing. In the area of the largest diameter of thestepped bore 24, the tubular end 55 of the cover 23 is sealed by meansof an O-ring 56 in relation to the stepped bore 24. Interposed betweenthe ring seal 25 and the O-ring 56, an inlet opening 57 is arranged onthe tubular end 55 of the cover 23 and establishes the connectionbetween the first duct 26 and the valve chamber 58 of the valve bore 20.Said valve chamber 58 communicates via a bore 59 provided on the tubularend 55 with the valve seats 32, 33 which, in turn, with the valve 19open, that is with the valve seats 32, 33 being spaced from one another,are connected with the distribution chamber 61 through the chamber 60and the smaller-diameter stepped bore 24.

At the end of the valve piston 22, which is on the bottom in FIG. 2 andis adjacent to the valve chamber 58, a cylindrical pin 62 is shaped,which penetrates the valve chamber 58 and the bore 59 and is providedwith a truncated cone 63 at its end projecting into the second chamber60, the said cone tapering upwardly in the drawing and its conicalperipheral surface forming the valve seat 32 of the valve piston 22.

In the valve assembly 19 according to FIG. 2, the second lever 45 ispivoted by way of its bore 46, in contrast to FIG. 1, on the peripheralsurface 64 of the first axis 38, while the first lever 36 is pivoted byway of its bore 37 on the cylinder-side outside surface 53 of the secondlever 45, so that the outside surface 53 forms the real axis for thefirst lever 36.

In contrast to FIG. 1, the first lever 36 in FIG. 2 is arranged belowthe second lever 45 and is confined by said towards the top. On the leg65 close to the second lever 45, the first actuating element 34 in theform of a first ramp is provided on the first lever 36, while directlyabove on the second leg 68 of the second lever 45 the second actuatingelement 35 is provided in the form of a second ramp, which is somewhat,or not at all, in sliding contact with the first ramp 34 in the closingposition of both levers 36, 45. That is to say, the second ramp 35 isalmost entirely turned out of the range of effect of the valve piston 22and, therefore, is not illustrated in a hatched way in the longitudinalcross-sectional view of the valve piston 22 in FIG. 2, but it can beseen in the background. Since the first ramp 34, too, has been turnedout of the drawing's plane, yet in opposite direction, it is notperceptible in full height.

As becomes apparent from FIG. 2, an annular gap (a) is provided betweenthe annular step 54, shaped on the cover 23 and forming the transitionto the first axis 38, and the end surface 66 close to the annular step54, which gap is required to the end that the first lever 36 candisplace axially downwardly in the drawing, once the first and thesecond lever 36, 45 are moved to adopt their position opening the valveassembly 19. When one of the two levers 36 and 45 is moved into itsposition closing the valve assembly 19, the valve piston 22 will bemoved upwardly in FIG. 2 by the force of the spring 30 alone and, indoing so, entrains the second lever 36 upwardly by way of its convexlyextending slide 42 and the outer boundary wall 67 provided on the leg65.

In FIG. 3, the support and the arrangement of the first and the secondlever 36, 45 have been omitted for the sake of simplicity, since thisarrangement corresponds to the arrangement illustrated in FIG. 2 andhence functions identically. The valve assembly 19, too, correspondsbasically to the valve assembly 19 shown in FIG. 2, except for that,instead of the conical design of the valve seats 32, 33 according toFIG. 2, a valve seat arrangement 32, 33 was chosen in FIG. 3, whichextends perpendicular to the longitudinal axis 39 of the valve piston22.

In order to accomplish a proper sealing of the valve piston 22 inrelation to the cover 23 in FIG. 3 as well, a seal 76 is providedbetween the valve seats 32, 33. Further, the cylinder pin 62 shown inFIG. 2 is substituted with a tubular extension having the same referencenumeral, in whose inner space 77 a compression spring 30 isincorporated. Said compression spring 30 takes support on the end 78 ofthe blind-end bore 79 confining the inner space 77 on the one side andon the annular step 27 on the other side.

Another difference compared to the valve assembly 19 according to FIG. 2resides in that the O-ring 56 is pressed by the cover 23 against anannular step 80 provided on the filter basket holding device 2. Like inFIG. 2, the cover 23 is tightly screwed into the stepped bore 24 havingthe largest diameter by a thread 81.

In FIG. 3, the valve piston 22 recedes in diameter in the area below thefirst duct 26 to ensure that the water can flow out through this portion82 to the distribution chamber 61 when the valve 19 is open. In order toprevent the occurrence of explosion-like ejections of water on thesecond filter 16 (FIG. 2), projecting ribs 83 are arranged below theportion 82 on the valve piston 22 being spread evenly over said'speriphery, the external diameter of which ribs extends up to the wall ofthe stepped bore. The slots 84 formed by two neighbouring ribs andextending along the longitudinal axis 39 of the valve piston 22 form areducing valve operating as a throttle in the passage from the firstduct 26 to the distribution chamber 61.

It can be gathered from FIG. 4 in conjunction with FIG. 1 that the freeend 40 of the first lever 36 abuts on an entraining surface 85configured as an entraining means on the projection 11 of the filterbasket holder. The position of the filter basket holder 1 shown in FIG.4, on which an outwardly stretching handle 86 is attached, representsespecially that position in which the filter basket holder i is to beintroduced with its projections 11 into the openings 90 of the bayonetlock arrangement, that means it is not yet brought into its closedposition by means of the groove 12. In this position, the entrainingsurface 85 abuts on the free end 40 of the first lever 36 straightly orafter a slight turning in the closing direction. In this position, thevalve piston 22 according to FIGS. 4 and 6 is still retained in itsclosing position by the abutment surface 70. The same applies to thesecond lever 45 once it has adopted the position it has in FIGS. 4 and6.

FIGS. 7 to 10 depict merely the two end positions possible for the twolevers 36 and 45. With the exception of the position shown in FIG. 7where the valve piston 22 assumes its opening position, the valve piston22 is always in its position closing the valve assembly 19 in FIGS. 8 to10. Since FIGS. 7 to 10 always illustrate the same component parts,reference numerals have been inserted in FIG. 7 only for the sake ofsimplicity.

The mode of function of the espresso coffee machine according to thepresent invention is as follows:

In FIGS. 1 and 4 to 6, the first lever 36 is still in its initialposition closing the valve assembly 19 and the second lever 45, too, isin its initial or, respectively, closing position closing the valveassembly 19. Both levers 36, 45 being in the position shown herein, nowater may flow through the first duct 26 to the distribution chamber 61,and hence not either to the brewing chamber 8. That is to say, espressocannot be made in this position. If the steam boiler is heated upnevertheless, and provided a second duct is arranged irrespective of thefirst duct 26, steam can flow out of said second duct via a steam valveand from there to a steam outlet so that cold beverages can be steamedand frothed. In order that the second duct delivers steam exclusively,the inlet of the second duct 26 must be arranged above the maximum waterlevel in the steam boiler.

When the filter basket holder 1 with its two diametrally oppositeprojections 11 is introduced by an axial movement into the groove 12 ofthe filter basket holding device 2, but is not yet turned, the positionof the filter basket holder 1 and of the first lever 36 shown in FIG. 4results. When, according to FIG. 4, the filter basket holder 1 is turnedcounterclockwise so far that the annular collar 9 of the filter basket 5is in pressure-tight abutment on the ring seal 14, the imaginary centreline 87 and thus the middle of the free end 14 of the first lever 36moves roughly until the dash-dot line 88. That is to say, correspondingto this angle of rotation, the filter basket holder 1 through itsentraining surface 85 has turned the free end 40 of the first lever 36.Since during this turning the first leg 65 and hence the abutmentsurface 70 as well as the first ramp 34 have also been turnedcounterclockwise, that means in the direction U according to FIG. 6, thefirst ramp 34--as is shown by the broken line 91 in FIG. 6--will now beat a distance below the free end 42 of the valve piston 22 without beingin sliding engagement with said; however, this is the case only becausethe second lever 45 was not turned in the direction U, that means, it isstill in its initial position closing the valve assembly 19 according toFIG. 4. When the filter basket holder 1 is introduced properly into thefilter basket holding device 2, this position permits that exclusivelysteam can be produced, which will then exit through the additional steamduct, as has been described already hereinabove, when, in addition, asteam valve not shown in the drawing is open.

Consequently, in order to be able to make an espresso coffee when thefilter basket holder 1 is introduced properly, the second lever 45 byway of its free end 50 must still be turned by hand counterclockwiseuntil it adopts the position shown by the centre line 89. On thisturning, the valve piston 22 can now slide over the abutment surface 73on the ramp 35 up to the abutment surface 72 according to the dash-lineillustration according to FIG. 5 so that, according to FIG. 1, it ismoved upwardly by the force of the compression spring 30 and its sealingseat 32 releases the sealing seat 33. The valve assembly 19 is open inthis position, and the pressurized water in the steam boiler can flowfrom the first duct 26 via the valve seats 32, 33 to the smallerdiameter of the valve bore 24, from where it propagates into thedistribution chamber 61 and flows evenly into the brewing chamber 8through the second filter 16. Since the hot water is subjected topressure, it will be pressed through espresso coffee grounds, providedthe brewing chamber 8 is filled therewith, and extracts the espressocoffee grounds. The espresso coffee is then conveyed through thepassages 7 provided on the bottom 6 of the filter 5 to the outlet 4,from where it can pour into a cup placed underneath.

When the filter basket holder 1 is turned out of the filter basketholding device 2 for removing the spent espresso coffee grounds afterespresso coffee has been made, a spring making catch on the first lever36, which is not illustrated in the drawing, must ensure that the firstlever 36 automatically returns to its position closing the valve 19,when the free end 40 of the first lever 36 is only loosely abutting onthe entraining surface 85, as is shown in FIG. 4.

If, for example, a user has not introduced the filter basket holder 1into the filter basket holding device 2, the first lever 36 willmaintain the position shown in FIGS. 1, 4 and 6, that means the valvepiston 22 is kept in its closing position by the abutment surface 70.When now a user operates by hand the Second lever 45 by way of its freeend 50 counterclockwise according to FIG. 4, that is in the direction U,it is possible that, although the second ramp 35 has released the valvepiston 22, the said is not either allowed to reach its opening position,since the abutment surface 70 continues to keep the valve piston 22 inits closing position when the filter basket holder 1 is not in itsproper seat.

That means that, although the second lever 45 was moved into its openingposition serving to make espresso coffee and characterized by the centreline 89, boiling water is not allowed to exit into the atmospherethrough the second filter 16 in case the filter basket holder 1 is notintroduced. Owing thereto, unpleasant burns will be avoided which occurif, for instance, the hand of a user is below the second filter 16, orclose thereto. Only after the filter basket holder 1 has assumed itsproper closing position, for the attaining of which the first lever 36must be turned about the angle A and, simultaneously, the second lever45 was moved into its opening position, is hot water allowed to exitthrough the valve assembly 19, however, in this case only through thebrewing chamber 8 which is shielded outwardly.

In the lever assembly 36, 45 coupled to the valve assembly 19 accordingto FIGS. 1 and 4 to 6, both levers 36, 45 are turned counterclockwise inorder to reach the open position of the valve assembly 19.

In the embodiment of a second valve assembly 19 with the pertaininglevers 36, 45 illustrated in FIGS. 2 and 7 to 10, the filter basketholder 1--like in the valve assembly 19 according to FIG. 1--is turnedinto a bayonet lock arrangement furnished with a right-hand thread, thatmeans likewise in counterclockwise direction. According to FIG. 2, thesecond lever 45 is turned clockwise, that is opposite to the first lever36, from its position closing the valve assembly 19 into its positionopening the valve assembly 19 for making espresso coffee. Thus, thesecond lever 45 does not assume the initial position shown in FIG. 4,but it adopts as initial position the end position on the centre line 89shown therein. However, for the sake of simplicity, a drawingcorresponding to the first embodiment according to FIG. 4 was notdrafted for the second embodiment. FIGS. 7 to 10 depict the fourpossible positions of the two levers 36, 45 in correlation to eachother.

In FIGS. 2 and 10, the filter basket holder 1 is not introduced into thefilter basket holding device 2, and the second lever 45 is disposed inits initial position which serves exclusively for producing steam. Inthis position, the valve piston 22 through the first leg 65 has liftedthe first lever 36 upwards by the amount (a) by virtue of the preloadingforce of the compression spring 30, since the second leg 68 of thesecond lever 45 is in its initial position and does not act upon thefirst leg 65. Consequently, it is only steam which can be produced inthis position, as has been described already in the first embodiment.

When, according to FIG. 9, the second lever 45 is turned clockwise, thatmeans from its position according to FIG. 10 to the left into theposition according to FIG. 9, the second ramp 35 will abut straight onthe first ramp 34, without displacing the first leg 65 and thus thefirst lever 36 according to FIG. 9 downwardly together with the valvepiston 22. That means, although the second lever 35 is in its endposition which serves to produce espresso coffee, no espresso coffee canbe .made, since the filter basket holder 1 is not introduced into thefilter basket holding device 2. In this position, again, only steam canbe produced.

When, in FIG. 8, the second lever 45 adopts its initial position, as isthe case in FIG. 10 as well, and when the filter basket holder 1 isintroduced properly into the filter basket holding device 2, it willentrain the first lever 36 in counterclockwise direction according toFIG. 1, consequently, to the right according to FIG. 8. However, sincethe first lever 36 is not acted upon by the second lever 45 due to thelatter being in its initial position, its boundary wall 67 will slidealong the convex slide 42 of the valve piston 22, without the firstlever 36 and, thus, the valve piston 22 being displaced downwardly bythe amount (a) according to FIG. 8. In this position, too, only steamcan be produced.

When the second lever 45, after turning to the left according to FIG. 7,has assumed its position which serves to make espresso coffee and whichcorresponds also to the position according to FIG. 9, and when now thefilter basket holder 1 is inserted into the filter basket holding device2 and is turned into its closing position, the entraining surface 85formed on the projection 11 will abut on the free end 40 of the firstlever 36--in a like manner as is illustrated in FIG. 1--and swivels itcounterclockwise, that is to the right in FIG. 7. First, its ramp 34will abut on the ramp 35, exactly as is the case in FIG. 9. When thefirst lever 36 is turned further, it displaces by the amount (a) towardsthe cover 23 on the housing and, in doing so, shifts the valve piston 22into the valve bore. According to FIG. 2, the truncated cone 63 liftswith its sealing seat 32 from the sealing seat 30 and releases the firstduct 26 to the distribution chamber 61. Hot water is now permitted toflow from the pressure reservoir into the brewing chamber, and espressocoffee can be made in case there is espresso coffee grounds in thebrewing chamber 8.

When, according to FIG. 7, one of the two levers 36, 45 is moved back toits initial position again, the valve piston 22 is caused by the forceof the spring to shift the first lever 36 upwards by the amount (a), andthe valve assembly 19 is closed again. To prevent the two legs 65, 68from being turned completely out of the range of effect of the valvepiston 22, the rotating movements of both levers 36, 45 are confined bystops not illustrated in the drawing. In order that the first lever 36always will move reliably back by the amount (a), what is normallyintended by the spring 30 and the first ramp 34, additionally, acompression or tension spring can still be provided, which makes catchdirectly on the first lever 36.

I claim:
 1. An espresso coffee machine comprising an electricallyheatable water heater, a filter basket holder, and a filter basketholding device which can be sealingly closed by introducing therein thefilter basket holder, said filter basket holder being subdivided by afilter into a brewing chamber that can be filled with coffee grounds andinto a pouring device arranged at its bottom, and wherein said coffeemachine further comprises a first duct and a second duct having a steamoutlet, said first duct opening into the filter basket holding device soas to connect the brewing chamber to the water heater, wherein saidfirst duct includes a throughflow controlling valve arranged therein andwhich is always closed when the filter basket holder is not insertedinto the filter basket holding device, wherein, after the insertion ofthe filter basket holder into the filter basket holding device, saidfilter basket holder causes the valve to move from its closed into anopen position, wherein a first actuating member is provided between thefilter basket holder and the valve which is actuated by the filterbasket holder to control the valve, and wherein steam can be taken fromthe espresso coffee machine through said second duct in order to steamand froth beverages, the said steam being produced in the water heateras well, and wherein in addition to the first actuating member, a secondactuating member is provided which also serves to control the valve, andwherein said first and second actuating members have open and closedpositions and wherein the valve opens only if both the first and thesecond actuating member have adopted their open position.
 2. An espressocoffee machine as claimed in claim 1 wherein the insertion of the filterbasket holder is performed by an axial displacement directed towards thefilter basket holding device, wherein the first actuating member is aturning lever, one end of which is so tilted about a point of supportdue to the axial displacement which occurs when the filter basketholding device is closed by the filter basket holder that an actuatingelement formed at the turning lever opens the valve.
 3. An espressocoffee machine as claimed in claim 1 further comprising a lockarrangement into which the filter basket holder is inserted and turnedin a closing movement to lock it therein and wherein the filter basketholder includes projections and the first actuating member comprises afirst lever rotatable about an axis and a first actuating element formedon said first lever, said first lever having a free end, wherein duringthe closing movement of the filter basket holder said projectionscontact the free end of the first lever and cause said first lever torotate about said axis in such a manner that said first actuatingelement opens the valve.
 4. An espresso coffee machine as claimed inclaim 3 wherein said filter basket holder includes a recess formedtherein and wherein when the filter basket holder is inserted into saidlock arrangement, the free end of the first lever is engaged into saidrecess.
 5. An espresso coffee machine as claimed in claim 3 wherein saidprojection provided on the filter basket holder functions as anentraining means for the free end of the first lever and wherein saidcoffee machine further comprises a spring acting on the first lever toautomatically return the first lever into an initial position closingthe valve when the filter basket holder is detached from the filterbasket holding device.
 6. An espresso coffee machine as claimed in claim3 wherein said filter basket holding device comprises a housing andwherein the valve comprises a valve piston, which is axially slidable inthe housing of the filter basket holding device, a valve seat that isopened and closed by the valve piston, and a spring acting upon thevalve piston for the purpose of automatic opening of the valve when thefilter basket holder is inserted and locked into said filter basketholding device, wherein a free end of the valve piston projects from thehousing of the filter basket holding device and is sealed in relation tothe housing, wherein with the valve closed, the first actuating elementformed on the first lever abuts on the free end of the piston andpresses said piston against a valve seat formed in the filter basketholding device, while, for opening the valve, the free end of the firstlever is turned by the filter basket holder such that the firstactuating element moves out of the range of effect of the valve pistonand the valve piston lifts from the valve seat.
 7. An espresso coffeemachine as claimed in claim 6 wherein an area of the actuating elementon the first lever facing the free end of the valve piston is a slidedesigned as a first ramp, and wherein the first ramp increases itsdistance from the free end of the valve piston in a closing direction ofthe filter basket holder.
 8. An espresso coffee machine as claimed inclaim 7 wherein adjacent to the first ramp on both sides is a slide inthe form of horizontally extending abutment surfaces which extendsperpendicular to a longitudinal axis of the valve piston, and whereinthe two horizontally extending abutment surfaces are disposed within aclosing angle (A) of the filter basket holder.
 9. An espresso coffeemachine as claimed in claim 8 wherein the filter basket holding deviceincludes a sealing joint and the filter basket holder includes a stoparranged radially outside of said sealing joint and wherein the firstlever extends substantially perpendicular to the longitudinal axis ofthe valve piston and the axis of the first lever, wherein the free endof the first lever extends towards the filter basket holder, is angledoff in relation to a horizontally extending area of the first lever, andextends in parallel to the longitudinal axis of the piston and the axisof the first lever, and wherein the free end of the first lever ismovable into operative engagement with the stop provided on the filterbasket holder.
 10. An espresso coffee machine as claimed in claim 9wherein the filter basket holder includes on a side thereof a lockelement which engages with the lock arrangement when the filter basketholder is coupled with the filter basket holding device, and wherein thelock element functions as a stop for the free end of the first lever.11. An espresso coffee machine as claimed in claim 1 further comprisinga lock arrangement, wherein the filter basket holding device comprises ahousing, the filter basket holder includes projections, the firstactuating member comprises a first actuating element, and the secondactuating member comprises a second actuating element, wherein both saidfirst and second actuating elements are movable so as to come intocontact with the valve, wherein when the filter basket holder isinserted into said filter basket holding device and turned theprojections engage into the lock arrangement, wherein the firstactuating member is a first lever and the second actuating member is asecond lever, both of said first and second levers being rotatable abouta first axis, wherein the valve comprises a valve piston axiallyslidable in the housing of the filter basket holding device, a valveseat which is opened and closed by the valve piston, and a spring actingupon the valve piston for the purpose of automatically opening of thevalve when the filter basket holder is locked into the filter basketholding device, wherein the valve piston at a free end thereof isadapted to be acted upon by each one of the first and second actuatingelements on the first and second levers, wherein the valve is sealed inrelation to the housing of the filter basket holding device, whereinwith the valve closed, the first and/or the second actuating elementabut with preload on the free end of the valve piston, while, foropening the valve, the first and the second actuating element aredisposed outside a range of effect on the free end of the valve pistonby a free end of the first lever being turned by the filter basketholder, and by the second actuating element, when turned, also movingout of a range of effect on the valve piston.
 12. An espresso coffeemachine as claimed in claim 11 wherein a first area on the firstactuating element and a second area on the second actuating elementwhich faces the free end of the valve piston, wherein the first area isa first slide designed as a first ramp and, the second area is a secondslide designed as a second ramp, and wherein a distance of the first andthe second slide is increased in relation to the free end of the valvepiston in a closing direction of the filter basket holder.
 13. Anespresso coffee machine as claimed in claim 12 wherein the first and thesecond ramp extend substantially in a same plane and in parallel to eachother in a closing position of the first and the second lever.
 14. Anespresso coffee machine as claimed in claim 13 wherein the second leveris pivoted on a second axis arranged on the first lever, and wherein thefirst and second ramps of the first and the second lever, respectively,when viewed from the first axis extend concentrically relative to eachother and radially one behind the other, and are opposed to the free endof the valve piston.
 15. An espresso coffee machine as claimed in claim13 wherein the second lever is operable by hand.
 16. An espresso coffeemachine as claimed in claim 11 wherein said first lever has a first boreand said second lever has a second bore and wherein said coffee machinefurther comprises a peg defining the first axis and supporting the firstlever by way of the first bore, and wherein the first lever comprises acylindrical peripheral surface on an outside wall of the first bore, onwhich surface the second lever is supported by way of the second bore.17. An espresso coffee machine as claimed in claim 16 wherein thedistance between the second ramp of the second lever and the first axisis less than the distance between the first ramp of the first lever andthe first axis.
 18. An espresso coffee machine as claimed in claim 17wherein the first lever is supported on the first axis above the secondlever, and wherein, outside the second lever in an area of the valvepiston, a first projection is formed on the first lever which representsthe first actuating element, which is directed towards the valve pistonand on the end surface of which close to the valve piston the first rampis provided.
 19. An espresso coffee machine as claimed in claim 1further comprising a lock arrangement, wherein the filter basket holdingdevice comprises a housing, the filter basket holder includesprojections the first actuating member comprises a first actuatingelement and the second actuating member comprises a second actuatingelement, both first and second actuating elements controlling the valve,wherein the filter basket holder is inserted by being turned by way ofprojections into the lock arrangement, wherein the first actuatingmember is a first lever and the second actuating member is a secondlever, both of said first and second levers being pivoted on a firstaxis, wherein the valve comprises a valve piston axially slidable in thehousing of the filter basket holding device and a valve seat which isopened and closed, respectively, by the valve piston, wherein the valvepiston on a free end thereof is acted upon by each one of said first andsecond actuating elements on the first and the second levers, whereinthe valve is sealed in relation to the housing, wherein the first leveradditionally is arranged to be slidable towards the valve piston,wherein after one of the first and second levers has turned into aposition serving to open the valve and the other of said first andsecond levers is also turned to assume an opening position serving toopen the valve, both first and second actuating elements of the firstand second levers act upon each other such that the first lever isdisplaced in the opening direction of the valve piston on a second axisarranged on the second lever and opens the valve thereby.
 20. Anespresso coffee machine as claimed in claim 19 wherein the area of thefirst actuating element on the first lever, which area faces the secondlever, is a first slide formed as a first ramp, and wherein the firstramp has a descent, when viewed in a closing direction of the filterbasket holder.
 21. An espresso coffee machine as claimed in claim 20wherein a second ramp designed as a second slide is provided on an areaof the second lever facing the first lever, and wherein the second rampextends substantially in parallel to the first ramp.
 22. An espressocoffee machine as claimed in claim 20 wherein the second lever ispivoted directly on the first axis, and the first lever is pivoted onthe second axis arranged on the second lever.
 23. An espresso coffeemachine as claimed in claims 21 or 22 wherein for opening the valve, thedirection of rotation of the first lever is opposite to the direction ofrotation of the second lever.
 24. An espresso coffee machine as claimedin claims 18 or 22 wherein the filter basket holding device includes asealing joint, wherein the filter basket holder includes a stop, whereinthe first lever extends substantially perpendicular to the longitudinalaxis of the valve piston and the first axis, wherein a free end of thefirst lever extends towards the filter basket holder, is angled off inrelation to a horizontally extending area of the first lever and extendsin parallel to the longitudinal axis of the piston and the first axis,and wherein the free end of the first lever is movable into operativeengagement with the stop on the filter basket holder, which stop isarranged on the filter basket holder radially outside the sealing jointon the filter basket holding device.
 25. An espresso coffee machine asclaimed in claim 20 wherein for opening the valve, both first and secondlevers have the same direction of rotation.
 26. An espresso coffeemachine as claimed in claim 1 further comprising a throttle operating asa reducing valve arranged in the first duct in the valve or downstreamthereof towards the brewing chamber.
 27. An espresso coffee machine asclaimed in claim 26 wherein an opening cross-section of the valve issized so large that it forms the throttle itself.